AIM:To evaluate the surgical outcomes of the perfluorocarbon liquid(PFCL)-assisted inverted multilayer internal limiting membrane(ILM)flaps covering technique in macular hole retinal detachment(MHRD)in high myopia wit...AIM:To evaluate the surgical outcomes of the perfluorocarbon liquid(PFCL)-assisted inverted multilayer internal limiting membrane(ILM)flaps covering technique in macular hole retinal detachment(MHRD)in high myopia with axial length(AL)≥30 mm.METHODS:In this retrospective,interventional,consecutive comparative study,44 MHRD eyes were divided into two groups:the PFCL-assisted inverted multilayer ILM flaps covering technique group(Group 1,21 eyes)and the ILM peeling group(Group 2,23 eyes).The follow-up period was>12mo.Postoperative outcomes,including retinal reattachment,macular hole(MH)closure,and bestcorrected visual acuity(BCVA),were assessed.Statistical analysis using the Mann–Whitney U test and Fisher’s exact test was conducted to compare differences between groups.RESULTS:There were no statistically significant differences in baseline preoperative clinical characteristics,including age,sex,AL,diopters,duration of symptom,lens status,posterior staphyloma presence and extent of RD.Retinal reattachment rates were higher in Group 1(90.5%)than in Group 2(82.6%),without statistical significance(P=0.667).MH closure rates were significantly higher in Group 1(85.7%)than in Group 2(17.4%;P<0.001).The Group-1 BCVA(logMAR)improved significantly from 2.13±0.91 preoperatively to 1.21±0.66 postoperatively(P=0.026).The Group 2 BCVA improved significantly from 1.91±0.53 preoperatively to 1.19±0.41 postoperatively(P=0.032).However,there were no significant differences in visual-acuity improvement between groups(P=0.460).CONCLUSION:This technique offers a more effective approach for improving MH closure rates and postoperative visual function in MHRD with AL≥30 mm in high myopia.展开更多
The flow control at low Reynolds numbers is one of the most promising technologies in the field of aerodynamics,and it is also an important source of the innovation for novel aircraft.In this study,a new way of nonlin...The flow control at low Reynolds numbers is one of the most promising technologies in the field of aerodynamics,and it is also an important source of the innovation for novel aircraft.In this study,a new way of nonlinear flow control by interaction between two flexible flaps is proposed,and their flow control mechanism is studied employing the self-constructed immersed boundary-lattice Boltzmann-finite element method(IB-LB-FEM).The effects of the difference in material properties and flap length between the two flexible flaps on the nonlinear flow control of the airfoil are discussed.It is suggested that the relationship between the deformation of the two flexible flaps and the evolution of the vortex under the fluid-structure interaction(FSI).It is shown that the upstream flexible flap plays a key role in the flow control of the two flexible flaps.The FSI effect of the upstream flexible flap will change the unsteady flow behind it and affect the deformation of the downstream flexible flap.Two flexible flaps with different material properties and different lengths will change their own FSI characteristics by the induced vortex,effectively suppressing the flow separation on the airfoil’s upper surface.The interaction of two flexible flaps plays an extremely important role in improving the autonomy and adjustability of flow control.The numerical results will provide a theoretical basis and technical guidance for the development and application of a new flap passive control technology.展开更多
Dear Editor,We present this case report which discusses a patient who underwent flap amputation after repeated attempts to resolve persistent and severe epithelial ingrowth following laser-assisted in situ keratomileu...Dear Editor,We present this case report which discusses a patient who underwent flap amputation after repeated attempts to resolve persistent and severe epithelial ingrowth following laser-assisted in situ keratomileusis(LASIK)surgery.Epithelial ingrowth is a known complication of LASIK surgery,typically manageable with minimal measures.However,severe cases may necessitate more aggressive interventions,such as flap amputation[1].LASIK is a widely performed refractive surgery with high success rates and excellent visual outcome[2].展开更多
Background:Penile augmentation through injectable substances is becoming increasingly common.A growing number of aesthetic clinics are developing penile enlargement procedures using various injectable materials.Althou...Background:Penile augmentation through injectable substances is becoming increasingly common.A growing number of aesthetic clinics are developing penile enlargement procedures using various injectable materials.Although these procedures are now performed in more controlled and medically supervised environments,their long-term outcomes remain poorly understood.The promotion of such medical treatments contributes to an increasing interest among adult males in self-injection as a method to alleviate psychological distress associated with penile size concerns.At the same time,access to injectable substances through unofficial or unregulated sources has become increasingly easy.Tor our knowledge,we report the first documented case of self-injection with Garamycin®(gentamicin)cream,contributing to the literature on the often multidisciplinary management of penile enlargement injections,a field still lacking well-established guidelines.Case Description:This case report describes a young patient who self-injected Garamycin®into the penis for the purpose of enlargement.He presented to our urology department with worsening symptoms,including severe and poorly tolerated pain.His primary request was prompt relief of pain while preserving,as much as possible,the aesthetic appearance and functional integrity of his penis.This case required a multi-stage surgical approach to salvage the penis and preserve both its structural integrity and functional outcome.Conclusions:To our knowledge,this case report documents the first reported instance of Garamycin®injection performed for the purpose of penile enlargement.It provides insight into the clinical course of such penile cream injections,demonstrates that a two-stage scrotal flap can achieve both functional and aesthetic outcomes,and highlights the importance of comprehensive management particularly addressing the traumatic impact of penile deformity secondary to inflammation and/or infection,as well as the body dysmorphic concerns often associated with these cases.展开更多
Focusing on civil aircraft flap skew detection design,this paper proposes a high-robustness monitoring design methodology to address insufficient monitor robustness that may trigger false alarms and disrupt airline op...Focusing on civil aircraft flap skew detection design,this paper proposes a high-robustness monitoring design methodology to address insufficient monitor robustness that may trigger false alarms and disrupt airline operations.Based on flap skew detection principles and threshold design criteria,the threshold range is defined with upper limit of maximum deformation under aerodynamic load and lower limit of sensor error margin and nominal flight deformation.Since the complex loading conditions of maximum flap differential deformation(max Δλ)during normal flight cannot be theoretically determined,probabilistic methods are employed:Flight test data from hundreds of sorties are analyzed using generalized extreme value distribution.Confidence levels are verified via Kolmogorov-Smirnov(K-S)hypothesis testing.Then probability density function of max Δλis established.The false alarm rate is calculated through cumulative probability values of max Δλat varying thresholds.Boundary conditions for false alarm rate are determined by safety assessment and dispatch reliability analysis.The derived monitoring threshold is verified against finite element analysis predictions and iron bird rig test.The results confirm the methodology’s validity,meeting all design objectives.展开更多
A high-precision CFD/CSD(Computational Fluid Dynamics/Computational Structural Dynamics)coupling method is developed to study the aeroelastic behavior and design the vibration reduction strategy of NTBT(New Type Blade...A high-precision CFD/CSD(Computational Fluid Dynamics/Computational Structural Dynamics)coupling method is developed to study the aeroelastic behavior and design the vibration reduction strategy of NTBT(New Type Blade-Tip)rotor with TEF(Trailing Edge Flap)technology in forward flight.In the aspect of CSD method,the closed-form dynamical governing equation is modified using Hamilton’s principle to consider the influence of the movable TEF,in which the NTBT geometric nonlinearity is considered through coordinate transformation by virtue of finite element method.In the aspect of CFD method,a moving-embedded grid method for rotor blades is developed to account for the dynamic deflection of TEF,in which the grid deformation is achieved through algebraic transformations,and a high-precision unsteady CFD method with 5th-order TENO(Targeted Essentially Non-Oscillatory)scheme is introduced to effectively simulate the rotor flowfield.Considering the computational efficiency,the loosely-coupling strategy is introduced to build up the CFD/CSD method.The validity of the coupling method is verified by comparing the computed aerodynamic loads,frequency spectrum,and structural loads with the referential or the experimental results of the typical model rotors.Based on that,the frequency,phase,and amplitude-sweeping parametric analyses of TEF are conducted thoroughly to reveal the influence mechanisms on the aeroelastic characteristics of NTBT rotor.Furthermore,an optimal control strategy is proposed to suppress the vibration intensity of hub loads,showing that the active vibration reduction method can effectively suppress the rotor hub vibratory intensity by over 40%in typical forward flight conditions.展开更多
Distally based perforator sural flaps from the posterolateral or posteromedial lower leg aspect are initially a neurofasciocutaneous flap that can be transferred reversely to the foot and ankle region with no need to ...Distally based perforator sural flaps from the posterolateral or posteromedial lower leg aspect are initially a neurofasciocutaneous flap that can be transferred reversely to the foot and ankle region with no need to harvest and sacrifice the deep major artery. These flaps are supplied by a perforating artery issued from the deep peroneal artery or the posterior tibial artery, and the chainlinked adipofascial neurovascular axis around the sural/saphenous nerve. It is a versatile and reliable technique for soft-tissue reconstruction of the heel and ankle region with 180-degrees rotation. In this paper, we present its developing history, vascular basis, surgical techniques including flap design and elevation, flap variations in pedicle and component, surgical indications, and illustrative case reports with different perforating vessels as pivot points for foot and ankle coverage.展开更多
BACKGROUND： Major complications after pancreaticoduo- denectomy are usually caused by a leaking pancreaticojejunal anastomosis. Omental flaps around various anastomoses were used to prevent the formation of fistula.
Objective The objective of this report was to demonstrate the clinical application of free flow-through anterolateral thigh flaps for the treatment of high-tension electrical wrist burns.Methods We collected the data ...Objective The objective of this report was to demonstrate the clinical application of free flow-through anterolateral thigh flaps for the treatment of high-tension electrical wrist burns.Methods We collected the data of 8 patients with high-tension electrical wrist burns admitted to Beijing Jishuitan Hospital from January 2014 to December 2018.The clinical and pathological data were extracted from electronic hospital medical records.We obtained follow-up information through clinic visits.Results The injury sites for all 8 patients were the wrists,specifically 5 right and 3 left wrists,all of which were on the flexor side.Five patients had ulnar artery embolism necrosis and patency,with injury to the radial artery.Two patients had ulnar and radial arterial embolization and necrosis.The last patient had ulnar arterial embolization and necrosis with a normal radial artery.After debridement,the wound area ranged from 12 cm×9 cm to 25 cm×16 cm.The diagnoses for the eight patients were type II to type III high-tension electrical wrist burns.Free flow-through anterolateral thigh flaps(combined with great saphenous vein transplantation if necessary)were used to repair the wounds.The prognosis for all patients was good after six months to one year of follow-up.Conclusion Treating wrist types II and III high-tension electrical burns is still challenging in clinical practice.The use of free flow-through anterolateral thigh flaps(combined with great saphenous vein transplantation if necessary)to repair the wound and to restore the blood supply for the hand at the same time is a good choice for treating severe wrist electrical burns.展开更多
There is long-standing debate about sensate versus non-sensate free microvascular flaps among microsurgeons. The principle of connecting not only the vascular supply, but also sensitive nerves, in free tissue transfer...There is long-standing debate about sensate versus non-sensate free microvascular flaps among microsurgeons. The principle of connecting not only the vascular supply, but also sensitive nerves, in free tissue transfer is attractive. However, increased operating time and partial spontaneous innervation led to the common decision to restrict microsurgical tissue transfer to the vascular anastomosis and to leave the nerves ＂untreated＂. Nevertheless, in special cases such as breast reconstruction or extremity reconstruction, the question about sensory nerve coaptation of the flaps remains open. We present our experience with free microvascular tissue transfer for breast and extremity reconstruction and compare the data with previous literature and conclude that most free flap surgeries do not benefit from nerve coaptation.展开更多
Abstract Morphing wing structures are widely considered among the most promising technologies for the improvement of aerodynamic performances in large civil aircraft.The controlled adaptation of the wing shape to exte...Abstract Morphing wing structures are widely considered among the most promising technologies for the improvement of aerodynamic performances in large civil aircraft.The controlled adaptation of the wing shape to external operative conditions naturally enables the maximization of aircraft aerodynamic efficiency,with positive fallouts on the amount of fuel burned and pollutant emissions.The benefits brought by morphing wings at aircraft level are accompanied by the criticalities of the enabling technologies,mainly involving weight penalties,overconsumption of electrical power,and safety issues.The attempt to solve such criticalities passes through the development of novel design approaches,ensuring the consolidation of reliable structural solutions that are adequately mature for certification and in-flight operations.In this work,the development phases of a multimodal camber morphing wing flap,tailored for large civil aircraft applications,are outlined with specific reference to the activities addressed by the author in the framework of the Clean Sky program.The flap is morphed according to target shapes depending on aircraft flight conditions and defined to enhance high-lift performances during takeoff and landing,as well as wing aerodynamic efficiency during cruise.An innovative system based on finger-like robotic ribs driven by electromechanical actuators is proposed as morphing-enabling technology;the maturation process of the device is then traced from the proof of concept to the consolidation of a true-scale demonstrator for pre-flight ground validation tests.A step-by-step approach involving the design and testing of intermediate demonstrators is then carried out to show the compliance of the adaptive system with industrial standards and safety requirements.The technical issues encountered during the development of each intermediate demonstrator are critically analyzed,and justifications are provided for all the adopted engineering solutions.Finally,the layout of the true-scale demonstrator is presented,with emphasis on the architectural strengths,enabling the forthcoming validation in real operative conditions.展开更多
Mesenchymal stem cells(MSCs), multipotential cells that reside within the bone marrow, can be induced to differentiate into various cells, such as osteoblasts, adipocytes, chondrocytes, vascular endothelial progenitor...Mesenchymal stem cells(MSCs), multipotential cells that reside within the bone marrow, can be induced to differentiate into various cells, such as osteoblasts, adipocytes, chondrocytes, vascular endothelial progenitor cells, and other cell types. MSCs are being widely studied as potential cell therapy agents due to their angiogenic properties, which have been well established by in vitro and in vivo researches. Within this context, MSCs therapy appears to hold substantial promise, particularly in the treatment of conditions involving skin grafts, pedicle flaps, as well as free flaps described in literatures. The purpose of this review is to report the new advances and mechanisms underlying MSCs therapy against skin flaps necrosis.展开更多
Gurney Flaps(GFs) are used for improving the performance of variable speed tail rotors. A validated analytical helicopter model able to predict the main and tail rotor power is utilized. The fixed height GF has substa...Gurney Flaps(GFs) are used for improving the performance of variable speed tail rotors. A validated analytical helicopter model able to predict the main and tail rotor power is utilized. The fixed height GF has substantially small influence on the tail rotor power in hover and low to medium speed forward flight, and can obtain significant power reduction in high speed flight.This ability can be enhanced by decreasing the tail rotor speed. With the deployment of GF, the collective pitch of the tail rotor decreases, and the maximum tail rotor thrust increases. The GF can compensate the reduction of the maximum thrust by the decrease in the tail rotor speed. The GF with a height of 5% of the chord length can almost remedy 50% of the thrust reduction introduced by decreasing 10% of the tail rotor speed. With the increase of GF height, the maximum thrust generated by the tail rotor increases. The GF with larger height can cause the increase in the tail rotor power in hover and low to medium speed flight. The retractable GF can obtain more power savings than the fixed height GF. However, the benefit is substantially small even in high speed flight. Considering the side effects introduced by the active GF, the fixed height GF may be more preferable. The mechanism for the retractable GF to generate more tail rotor thrust is to increase the lift in advancing side due to the higher dynamic pressure.展开更多
· AIM: To reconstruct the extensive full-thickness defects of eyelids is a challenge for the plastic surgeon because of their complex anatomy and special functions.This article presents and discusses an improved ...· AIM: To reconstruct the extensive full-thickness defects of eyelids is a challenge for the plastic surgeon because of their complex anatomy and special functions.This article presents and discusses an improved surgical technique in which the orbicularis oculi myocutaneous flap is rotated through a "subcutaneous tunnel" in conjunction with a palatal mucosal graft employed for lining.·METHODS: Data from 22 eyes with extensive full-thickness eyelid defects from various causes between2009 and 2013 were analyzed in this study. After the different layers of eyelid were separated completely, a temporally based orbicularis oculi myocutaneous flap was designed following fishtail lines and was mobilized,leaving the base of the pedicle intact with a submuscular tissue attachment. The flap was then rotated through a "subcutaneous tunnel" to the defect, and the donor site was closed primarily. Posterior lamellar reconstruction was performed with a mucosal graft harvested from the hard palate.·RESULTS: All the flaps were survived without any healing problems. There was no corneal irritation, flap contraction, or significant donor-site morbidity in the follow-up period. The incision scars were almost invisible.The defects were repaired completely, and the evaluations showed satisfactory function and appearance.·CONCLUSION: This technique is an improved singlestage operation and can be applied to repair large, full-thickness eyelid defects from various causes. With our method, the functional and aesthetic results can be obtained in either the upper or lower eyelids.展开更多
·AIM: To provide superior cosmetic results and reduce complications, unlike traditional evisceration coupled with implant insertion technique and its modifications,we have developed a novel and simple technique f...·AIM: To provide superior cosmetic results and reduce complications, unlike traditional evisceration coupled with implant insertion technique and its modifications,we have developed a novel and simple technique for anophthalmic patients.·METHODS: All patients who underwent the scleral-muscle flaps procedure in evisceration with the placement of hydroxyapatite implant were included in the study. Main outcome measures were complications such as exposure, infection, chemosis, conjunctival inclusion cysts, granulomas. Meanwhile, implant motility was indirectly measured and the results were collected and analyzed.· RESULTS: A total of twenty-eight patients were enrolled in the study. Eighteen were men(64.29%) and ten were women(35.71%). Ages ranged from 18 to 65y(mean age, 32 years old). Mean follow-up was 12.32mo(range, 9-16mo). All patients received a hydroxyapatite implant. The average diameter of the implant was 19.29 ±1.36 mm(range, 18-22 mm). Minor complications occurred in 3 patients, and a major complication was observed in 1 patient. Mean motility were 11.04 ±1.45 mm horizontally(range, 7-14 mm) and 8.57 ±1.50 mm vertically(range, 5-12 mm).·CONCLUSION: The sclera-muscle flaps technique in evisceration with hydroxyapatite implantation is simple and practical that eases the surgical procedure, enables a proper size hydroxyapatite implantation, distinctively reduces complications and provides superior surgery results, especially the motility of the implant.展开更多
The effect of Gurney flaps with different heights on the S809 airfoil and NH1500 blade is numerically simulated.The influence of the Gurney flap is analyzed at different wind speeds and the comparison of the aerodynam...The effect of Gurney flaps with different heights on the S809 airfoil and NH1500 blade is numerically simulated.The influence of the Gurney flap is analyzed at different wind speeds and the comparison of the aerodynamic performance is given between the blades with and without the Gurney flap.The results demonstrate that a Gurney flap added on the blade can greatly increase the efficiency of the wind turbine especially at high wind speeds.展开更多
Objective To assess clinical effectiveness of using bilateral pectoralis major or plus rectus abdominis muscle flaps in treating deep sternal wound infection(DSWI) following median sternotomy. Methods Between January ...Objective To assess clinical effectiveness of using bilateral pectoralis major or plus rectus abdominis muscle flaps in treating deep sternal wound infection(DSWI) following median sternotomy. Methods Between January 2009 and December 2013, 19 patients with DSWI after median sternotomy for cardiac surgery were admitted to our hospital, including 14 males(73.7%) and 5 females(26.3%), aged 55±13(18-78) years. According to the Pairolero classification of infected median sternotomies, 3(15.8%) patients were type II, and the other 16(84.2%) were type III. Surgical procedure consisted of adequate debridement of infected sternum, costal cartilage, granulation, steel wires, suture residues and other foreign substances. Sternal reconstruction used the bilateral pectoralis major or plus rectus abdominis muscle flaps to obliterate dead space. The drainage tubes were placed and connected to a negative pressure generator for adequate drainage. Results There were no intraoperative deaths. In 15 patients(78.9%), bilateral pectoral muscle flaps were mobilized sufficiently to cover and stabilize the defect created by wound debridement. 4 patients(21.0%) needed bilateral pectoral muscle flaps plus rectus abdominis muscle flaps because their pectoralis major muscle flaps could not reach the lowest portion of the wound. 2 patients(10.5%) presented with subcutaneous infection, and 3 patients(15.8%) had hematoma. They recovered following local debridement and medication. 17 patients(89.5%) were examined at follow-up 12 months later, all healed and having stable sternum. No patients showed infection recurrence during the follow-up period over 12 months. Conclusion DSWI following median sternotomy may be effectively managed with adequate debridement of infected tissues and reconstruction with bilateral pectoralis major muscle or plus rectus abdominis muscle flap transposition.展开更多
BACKGROUND In daily life and work,there are more and more patients with trauma to the hand,which often results in skin and soft tissue defects.Although there are many repair methods,the function and appearance of the ...BACKGROUND In daily life and work,there are more and more patients with trauma to the hand,which often results in skin and soft tissue defects.Although there are many repair methods,the function and appearance of the fingers will be adversely affected if the repair is inadequate.CASE SUMMARY In the present report we describe an 18-year-old male patient whose right hand was mangled by a machine.X-ray imaging showed that a right hand bone(middle finger)was absent and the alignment was poor.After hospitalization,he was diagnosed with a severe right hand injury,skin and soft tissue defects,partial finger defects,and a skin degloving injury.He underwent reconstructive surgery with anterolateral thigh and ilioinguinal flaps.After two repair operations,satisfactory results were obtained,including good fracture healing,good skin flap shape,and good wrist joint function.CONCLUSION This case highlights the good effect of anterolateral thigh and ilioinguinal flaps repair technique on severe palm injury.展开更多
Objective： To study the possibility of using portions of deepithelialized myocutaneous flaps to the reconstruction of thoracic tracheal defects after resection of a large tumor. Methods： From June 2007 to June 2012,...Objective： To study the possibility of using portions of deepithelialized myocutaneous flaps to the reconstruction of thoracic tracheal defects after resection of a large tumor. Methods： From June 2007 to June 2012, five cases of defects of the thoracic trachea were reconstructed by applying portions of deepithelialized myocutaneous flaps. The patients were 27-61 years old with 4 male cases and 1 female. The cervical trachea ranged in diameter from 4-8.5 cm with circumferences of approximately 1/3-2/5 of the bronchial circumference. Results： M1 five patients with thoracic tracheal defects after resection of a large tumor were cured of portions of deepithelialized myocutaneous flaps, with no tracheal stricture remaining and vomica successfully eliminated. During the first 1 to 3 months after the operation, bronchoscopy showed that the tracheal lumens were smooth, and the visible skin of the musculocutaneous flaps became gray and exhibited a small amount of white discharge. Conclusions： Despite this being a small series and short follow-up, this thoracic tracheal reconstruction with portions of deepithelialized myocutaneous flaps shows encouraging preliminary results and could be an alternative to other methods for the treatment of carefully selected patients with thoracic tracheal defects.展开更多
基金Supported by Research Incubation Fund of Xi’an People’s Hospital(Xi’an Fourth Hospital)(No.FZ-58).
文摘AIM:To evaluate the surgical outcomes of the perfluorocarbon liquid(PFCL)-assisted inverted multilayer internal limiting membrane(ILM)flaps covering technique in macular hole retinal detachment(MHRD)in high myopia with axial length(AL)≥30 mm.METHODS:In this retrospective,interventional,consecutive comparative study,44 MHRD eyes were divided into two groups:the PFCL-assisted inverted multilayer ILM flaps covering technique group(Group 1,21 eyes)and the ILM peeling group(Group 2,23 eyes).The follow-up period was>12mo.Postoperative outcomes,including retinal reattachment,macular hole(MH)closure,and bestcorrected visual acuity(BCVA),were assessed.Statistical analysis using the Mann–Whitney U test and Fisher’s exact test was conducted to compare differences between groups.RESULTS:There were no statistically significant differences in baseline preoperative clinical characteristics,including age,sex,AL,diopters,duration of symptom,lens status,posterior staphyloma presence and extent of RD.Retinal reattachment rates were higher in Group 1(90.5%)than in Group 2(82.6%),without statistical significance(P=0.667).MH closure rates were significantly higher in Group 1(85.7%)than in Group 2(17.4%;P<0.001).The Group-1 BCVA(logMAR)improved significantly from 2.13±0.91 preoperatively to 1.21±0.66 postoperatively(P=0.026).The Group 2 BCVA improved significantly from 1.91±0.53 preoperatively to 1.19±0.41 postoperatively(P=0.032).However,there were no significant differences in visual-acuity improvement between groups(P=0.460).CONCLUSION:This technique offers a more effective approach for improving MH closure rates and postoperative visual function in MHRD with AL≥30 mm in high myopia.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.92371201,52192633,11872293,and 92152301)the Natural Science Basic Research Program of Shaanxi(Grant Nos.2024JC-YBQN-0008,and 2022JC-03)+1 种基金Shaanxi Key Research and Development Program(Grant No.2022ZDLGY02-07)the Joint Natural Science Foundation of China with Guangdong Province for TianHe-II Supercomputer Resources,and the Research Start-up Foundation of Xi’an University of Science and Technology for the High-Level Talent.
文摘The flow control at low Reynolds numbers is one of the most promising technologies in the field of aerodynamics,and it is also an important source of the innovation for novel aircraft.In this study,a new way of nonlinear flow control by interaction between two flexible flaps is proposed,and their flow control mechanism is studied employing the self-constructed immersed boundary-lattice Boltzmann-finite element method(IB-LB-FEM).The effects of the difference in material properties and flap length between the two flexible flaps on the nonlinear flow control of the airfoil are discussed.It is suggested that the relationship between the deformation of the two flexible flaps and the evolution of the vortex under the fluid-structure interaction(FSI).It is shown that the upstream flexible flap plays a key role in the flow control of the two flexible flaps.The FSI effect of the upstream flexible flap will change the unsteady flow behind it and affect the deformation of the downstream flexible flap.Two flexible flaps with different material properties and different lengths will change their own FSI characteristics by the induced vortex,effectively suppressing the flow separation on the airfoil’s upper surface.The interaction of two flexible flaps plays an extremely important role in improving the autonomy and adjustability of flow control.The numerical results will provide a theoretical basis and technical guidance for the development and application of a new flap passive control technology.
文摘Dear Editor,We present this case report which discusses a patient who underwent flap amputation after repeated attempts to resolve persistent and severe epithelial ingrowth following laser-assisted in situ keratomileusis(LASIK)surgery.Epithelial ingrowth is a known complication of LASIK surgery,typically manageable with minimal measures.However,severe cases may necessitate more aggressive interventions,such as flap amputation[1].LASIK is a widely performed refractive surgery with high success rates and excellent visual outcome[2].
文摘Background:Penile augmentation through injectable substances is becoming increasingly common.A growing number of aesthetic clinics are developing penile enlargement procedures using various injectable materials.Although these procedures are now performed in more controlled and medically supervised environments,their long-term outcomes remain poorly understood.The promotion of such medical treatments contributes to an increasing interest among adult males in self-injection as a method to alleviate psychological distress associated with penile size concerns.At the same time,access to injectable substances through unofficial or unregulated sources has become increasingly easy.Tor our knowledge,we report the first documented case of self-injection with Garamycin®(gentamicin)cream,contributing to the literature on the often multidisciplinary management of penile enlargement injections,a field still lacking well-established guidelines.Case Description:This case report describes a young patient who self-injected Garamycin®into the penis for the purpose of enlargement.He presented to our urology department with worsening symptoms,including severe and poorly tolerated pain.His primary request was prompt relief of pain while preserving,as much as possible,the aesthetic appearance and functional integrity of his penis.This case required a multi-stage surgical approach to salvage the penis and preserve both its structural integrity and functional outcome.Conclusions:To our knowledge,this case report documents the first reported instance of Garamycin®injection performed for the purpose of penile enlargement.It provides insight into the clinical course of such penile cream injections,demonstrates that a two-stage scrotal flap can achieve both functional and aesthetic outcomes,and highlights the importance of comprehensive management particularly addressing the traumatic impact of penile deformity secondary to inflammation and/or infection,as well as the body dysmorphic concerns often associated with these cases.
文摘Focusing on civil aircraft flap skew detection design,this paper proposes a high-robustness monitoring design methodology to address insufficient monitor robustness that may trigger false alarms and disrupt airline operations.Based on flap skew detection principles and threshold design criteria,the threshold range is defined with upper limit of maximum deformation under aerodynamic load and lower limit of sensor error margin and nominal flight deformation.Since the complex loading conditions of maximum flap differential deformation(max Δλ)during normal flight cannot be theoretically determined,probabilistic methods are employed:Flight test data from hundreds of sorties are analyzed using generalized extreme value distribution.Confidence levels are verified via Kolmogorov-Smirnov(K-S)hypothesis testing.Then probability density function of max Δλis established.The false alarm rate is calculated through cumulative probability values of max Δλat varying thresholds.Boundary conditions for false alarm rate are determined by safety assessment and dispatch reliability analysis.The derived monitoring threshold is verified against finite element analysis predictions and iron bird rig test.The results confirm the methodology’s validity,meeting all design objectives.
基金supported by the National Natural Science Foundation of China(Nos.12102186,12472237)the Young Elite Scientists Sponsorship Program by CAST,China(No.2022QNRC001)+1 种基金the National Key Laboratory Foundation of China(No.61422202201)the Aeronautical Science Foundation of China(No.2024Z010052002)。
文摘A high-precision CFD/CSD(Computational Fluid Dynamics/Computational Structural Dynamics)coupling method is developed to study the aeroelastic behavior and design the vibration reduction strategy of NTBT(New Type Blade-Tip)rotor with TEF(Trailing Edge Flap)technology in forward flight.In the aspect of CSD method,the closed-form dynamical governing equation is modified using Hamilton’s principle to consider the influence of the movable TEF,in which the NTBT geometric nonlinearity is considered through coordinate transformation by virtue of finite element method.In the aspect of CFD method,a moving-embedded grid method for rotor blades is developed to account for the dynamic deflection of TEF,in which the grid deformation is achieved through algebraic transformations,and a high-precision unsteady CFD method with 5th-order TENO(Targeted Essentially Non-Oscillatory)scheme is introduced to effectively simulate the rotor flowfield.Considering the computational efficiency,the loosely-coupling strategy is introduced to build up the CFD/CSD method.The validity of the coupling method is verified by comparing the computed aerodynamic loads,frequency spectrum,and structural loads with the referential or the experimental results of the typical model rotors.Based on that,the frequency,phase,and amplitude-sweeping parametric analyses of TEF are conducted thoroughly to reveal the influence mechanisms on the aeroelastic characteristics of NTBT rotor.Furthermore,an optimal control strategy is proposed to suppress the vibration intensity of hub loads,showing that the active vibration reduction method can effectively suppress the rotor hub vibratory intensity by over 40%in typical forward flight conditions.
基金Supported by Natural Science Fundation of China(NSFC),No.81271993Shanghai Municipal Health and Family Planning Commission,No.201440352
文摘Distally based perforator sural flaps from the posterolateral or posteromedial lower leg aspect are initially a neurofasciocutaneous flap that can be transferred reversely to the foot and ankle region with no need to harvest and sacrifice the deep major artery. These flaps are supplied by a perforating artery issued from the deep peroneal artery or the posterior tibial artery, and the chainlinked adipofascial neurovascular axis around the sural/saphenous nerve. It is a versatile and reliable technique for soft-tissue reconstruction of the heel and ankle region with 180-degrees rotation. In this paper, we present its developing history, vascular basis, surgical techniques including flap design and elevation, flap variations in pedicle and component, surgical indications, and illustrative case reports with different perforating vessels as pivot points for foot and ankle coverage.
文摘BACKGROUND： Major complications after pancreaticoduo- denectomy are usually caused by a leaking pancreaticojejunal anastomosis. Omental flaps around various anastomoses were used to prevent the formation of fistula.
基金Beijing Jishuitan Hospital Nova Program Funding[XKXX201617]。
文摘Objective The objective of this report was to demonstrate the clinical application of free flow-through anterolateral thigh flaps for the treatment of high-tension electrical wrist burns.Methods We collected the data of 8 patients with high-tension electrical wrist burns admitted to Beijing Jishuitan Hospital from January 2014 to December 2018.The clinical and pathological data were extracted from electronic hospital medical records.We obtained follow-up information through clinic visits.Results The injury sites for all 8 patients were the wrists,specifically 5 right and 3 left wrists,all of which were on the flexor side.Five patients had ulnar artery embolism necrosis and patency,with injury to the radial artery.Two patients had ulnar and radial arterial embolization and necrosis.The last patient had ulnar arterial embolization and necrosis with a normal radial artery.After debridement,the wound area ranged from 12 cm×9 cm to 25 cm×16 cm.The diagnoses for the eight patients were type II to type III high-tension electrical wrist burns.Free flow-through anterolateral thigh flaps(combined with great saphenous vein transplantation if necessary)were used to repair the wounds.The prognosis for all patients was good after six months to one year of follow-up.Conclusion Treating wrist types II and III high-tension electrical burns is still challenging in clinical practice.The use of free flow-through anterolateral thigh flaps(combined with great saphenous vein transplantation if necessary)to repair the wound and to restore the blood supply for the hand at the same time is a good choice for treating severe wrist electrical burns.
文摘There is long-standing debate about sensate versus non-sensate free microvascular flaps among microsurgeons. The principle of connecting not only the vascular supply, but also sensitive nerves, in free tissue transfer is attractive. However, increased operating time and partial spontaneous innervation led to the common decision to restrict microsurgical tissue transfer to the vascular anastomosis and to leave the nerves ＂untreated＂. Nevertheless, in special cases such as breast reconstruction or extremity reconstruction, the question about sensory nerve coaptation of the flaps remains open. We present our experience with free microvascular tissue transfer for breast and extremity reconstruction and compare the data with previous literature and conclude that most free flap surgeries do not benefit from nerve coaptation.
基金The researches described in this paper have been carried out in the framework of the Clean Sky Green Regional Aircraft ITD(Low Noise Configuration Domain)and Airgreen2 projectsThe activities have gratefully received funding respectively from the Cleans Sky and the Clean Sly 2 Joint Undertaking,under the European Union FP7 and H2020 research and innovation programs,Grant Agreements No.CSJU-GAM-GRA-2008-001 and No.807089—REG GAM 2018—H2020-IBA-CS2-GAMS-2017.
文摘Abstract Morphing wing structures are widely considered among the most promising technologies for the improvement of aerodynamic performances in large civil aircraft.The controlled adaptation of the wing shape to external operative conditions naturally enables the maximization of aircraft aerodynamic efficiency,with positive fallouts on the amount of fuel burned and pollutant emissions.The benefits brought by morphing wings at aircraft level are accompanied by the criticalities of the enabling technologies,mainly involving weight penalties,overconsumption of electrical power,and safety issues.The attempt to solve such criticalities passes through the development of novel design approaches,ensuring the consolidation of reliable structural solutions that are adequately mature for certification and in-flight operations.In this work,the development phases of a multimodal camber morphing wing flap,tailored for large civil aircraft applications,are outlined with specific reference to the activities addressed by the author in the framework of the Clean Sky program.The flap is morphed according to target shapes depending on aircraft flight conditions and defined to enhance high-lift performances during takeoff and landing,as well as wing aerodynamic efficiency during cruise.An innovative system based on finger-like robotic ribs driven by electromechanical actuators is proposed as morphing-enabling technology;the maturation process of the device is then traced from the proof of concept to the consolidation of a true-scale demonstrator for pre-flight ground validation tests.A step-by-step approach involving the design and testing of intermediate demonstrators is then carried out to show the compliance of the adaptive system with industrial standards and safety requirements.The technical issues encountered during the development of each intermediate demonstrator are critically analyzed,and justifications are provided for all the adopted engineering solutions.Finally,the layout of the true-scale demonstrator is presented,with emphasis on the architectural strengths,enabling the forthcoming validation in real operative conditions.
文摘Mesenchymal stem cells(MSCs), multipotential cells that reside within the bone marrow, can be induced to differentiate into various cells, such as osteoblasts, adipocytes, chondrocytes, vascular endothelial progenitor cells, and other cell types. MSCs are being widely studied as potential cell therapy agents due to their angiogenic properties, which have been well established by in vitro and in vivo researches. Within this context, MSCs therapy appears to hold substantial promise, particularly in the treatment of conditions involving skin grafts, pedicle flaps, as well as free flaps described in literatures. The purpose of this review is to report the new advances and mechanisms underlying MSCs therapy against skin flaps necrosis.
基金supported from the National Natural Science Foundation of China (No. 11472129)the Science and Technology on Rotorcraft Aeromechanics Laboratory Foundation of China (No. 6142220050416220002)+2 种基金the Foundation of Graduate Innovation Center in NUAA of China. (No. KFJJ20170102)the Fundamental Research Funds for the Central Universities of Chinaa project funded by the Priority Academic Program Development of Jiangsu Higher Educational Institution of China
文摘Gurney Flaps(GFs) are used for improving the performance of variable speed tail rotors. A validated analytical helicopter model able to predict the main and tail rotor power is utilized. The fixed height GF has substantially small influence on the tail rotor power in hover and low to medium speed forward flight, and can obtain significant power reduction in high speed flight.This ability can be enhanced by decreasing the tail rotor speed. With the deployment of GF, the collective pitch of the tail rotor decreases, and the maximum tail rotor thrust increases. The GF can compensate the reduction of the maximum thrust by the decrease in the tail rotor speed. The GF with a height of 5% of the chord length can almost remedy 50% of the thrust reduction introduced by decreasing 10% of the tail rotor speed. With the increase of GF height, the maximum thrust generated by the tail rotor increases. The GF with larger height can cause the increase in the tail rotor power in hover and low to medium speed flight. The retractable GF can obtain more power savings than the fixed height GF. However, the benefit is substantially small even in high speed flight. Considering the side effects introduced by the active GF, the fixed height GF may be more preferable. The mechanism for the retractable GF to generate more tail rotor thrust is to increase the lift in advancing side due to the higher dynamic pressure.
基金Supported by Jilin Province Science and Techology Development Plan Project(No.20150414032GH)
文摘· AIM: To reconstruct the extensive full-thickness defects of eyelids is a challenge for the plastic surgeon because of their complex anatomy and special functions.This article presents and discusses an improved surgical technique in which the orbicularis oculi myocutaneous flap is rotated through a "subcutaneous tunnel" in conjunction with a palatal mucosal graft employed for lining.·METHODS: Data from 22 eyes with extensive full-thickness eyelid defects from various causes between2009 and 2013 were analyzed in this study. After the different layers of eyelid were separated completely, a temporally based orbicularis oculi myocutaneous flap was designed following fishtail lines and was mobilized,leaving the base of the pedicle intact with a submuscular tissue attachment. The flap was then rotated through a "subcutaneous tunnel" to the defect, and the donor site was closed primarily. Posterior lamellar reconstruction was performed with a mucosal graft harvested from the hard palate.·RESULTS: All the flaps were survived without any healing problems. There was no corneal irritation, flap contraction, or significant donor-site morbidity in the follow-up period. The incision scars were almost invisible.The defects were repaired completely, and the evaluations showed satisfactory function and appearance.·CONCLUSION: This technique is an improved singlestage operation and can be applied to repair large, full-thickness eyelid defects from various causes. With our method, the functional and aesthetic results can be obtained in either the upper or lower eyelids.
文摘·AIM: To provide superior cosmetic results and reduce complications, unlike traditional evisceration coupled with implant insertion technique and its modifications,we have developed a novel and simple technique for anophthalmic patients.·METHODS: All patients who underwent the scleral-muscle flaps procedure in evisceration with the placement of hydroxyapatite implant were included in the study. Main outcome measures were complications such as exposure, infection, chemosis, conjunctival inclusion cysts, granulomas. Meanwhile, implant motility was indirectly measured and the results were collected and analyzed.· RESULTS: A total of twenty-eight patients were enrolled in the study. Eighteen were men(64.29%) and ten were women(35.71%). Ages ranged from 18 to 65y(mean age, 32 years old). Mean follow-up was 12.32mo(range, 9-16mo). All patients received a hydroxyapatite implant. The average diameter of the implant was 19.29 ±1.36 mm(range, 18-22 mm). Minor complications occurred in 3 patients, and a major complication was observed in 1 patient. Mean motility were 11.04 ±1.45 mm horizontally(range, 7-14 mm) and 8.57 ±1.50 mm vertically(range, 5-12 mm).·CONCLUSION: The sclera-muscle flaps technique in evisceration with hydroxyapatite implantation is simple and practical that eases the surgical procedure, enables a proper size hydroxyapatite implantation, distinctively reduces complications and provides superior surgery results, especially the motility of the implant.
基金Supported by the National Natural Science Foundation of China(11172135)the National Basic Research Program of China(″973″Program)(2014CB046200)the Fundamental Research Funds for the Central Universities(NS2012036,NJ20130008)
文摘The effect of Gurney flaps with different heights on the S809 airfoil and NH1500 blade is numerically simulated.The influence of the Gurney flap is analyzed at different wind speeds and the comparison of the aerodynamic performance is given between the blades with and without the Gurney flap.The results demonstrate that a Gurney flap added on the blade can greatly increase the efficiency of the wind turbine especially at high wind speeds.
文摘Objective To assess clinical effectiveness of using bilateral pectoralis major or plus rectus abdominis muscle flaps in treating deep sternal wound infection(DSWI) following median sternotomy. Methods Between January 2009 and December 2013, 19 patients with DSWI after median sternotomy for cardiac surgery were admitted to our hospital, including 14 males(73.7%) and 5 females(26.3%), aged 55±13(18-78) years. According to the Pairolero classification of infected median sternotomies, 3(15.8%) patients were type II, and the other 16(84.2%) were type III. Surgical procedure consisted of adequate debridement of infected sternum, costal cartilage, granulation, steel wires, suture residues and other foreign substances. Sternal reconstruction used the bilateral pectoralis major or plus rectus abdominis muscle flaps to obliterate dead space. The drainage tubes were placed and connected to a negative pressure generator for adequate drainage. Results There were no intraoperative deaths. In 15 patients(78.9%), bilateral pectoral muscle flaps were mobilized sufficiently to cover and stabilize the defect created by wound debridement. 4 patients(21.0%) needed bilateral pectoral muscle flaps plus rectus abdominis muscle flaps because their pectoralis major muscle flaps could not reach the lowest portion of the wound. 2 patients(10.5%) presented with subcutaneous infection, and 3 patients(15.8%) had hematoma. They recovered following local debridement and medication. 17 patients(89.5%) were examined at follow-up 12 months later, all healed and having stable sternum. No patients showed infection recurrence during the follow-up period over 12 months. Conclusion DSWI following median sternotomy may be effectively managed with adequate debridement of infected tissues and reconstruction with bilateral pectoralis major muscle or plus rectus abdominis muscle flap transposition.
文摘BACKGROUND In daily life and work,there are more and more patients with trauma to the hand,which often results in skin and soft tissue defects.Although there are many repair methods,the function and appearance of the fingers will be adversely affected if the repair is inadequate.CASE SUMMARY In the present report we describe an 18-year-old male patient whose right hand was mangled by a machine.X-ray imaging showed that a right hand bone(middle finger)was absent and the alignment was poor.After hospitalization,he was diagnosed with a severe right hand injury,skin and soft tissue defects,partial finger defects,and a skin degloving injury.He underwent reconstructive surgery with anterolateral thigh and ilioinguinal flaps.After two repair operations,satisfactory results were obtained,including good fracture healing,good skin flap shape,and good wrist joint function.CONCLUSION This case highlights the good effect of anterolateral thigh and ilioinguinal flaps repair technique on severe palm injury.
文摘Objective： To study the possibility of using portions of deepithelialized myocutaneous flaps to the reconstruction of thoracic tracheal defects after resection of a large tumor. Methods： From June 2007 to June 2012, five cases of defects of the thoracic trachea were reconstructed by applying portions of deepithelialized myocutaneous flaps. The patients were 27-61 years old with 4 male cases and 1 female. The cervical trachea ranged in diameter from 4-8.5 cm with circumferences of approximately 1/3-2/5 of the bronchial circumference. Results： M1 five patients with thoracic tracheal defects after resection of a large tumor were cured of portions of deepithelialized myocutaneous flaps, with no tracheal stricture remaining and vomica successfully eliminated. During the first 1 to 3 months after the operation, bronchoscopy showed that the tracheal lumens were smooth, and the visible skin of the musculocutaneous flaps became gray and exhibited a small amount of white discharge. Conclusions： Despite this being a small series and short follow-up, this thoracic tracheal reconstruction with portions of deepithelialized myocutaneous flaps shows encouraging preliminary results and could be an alternative to other methods for the treatment of carefully selected patients with thoracic tracheal defects.
